Gamma-butyrolactones are used in the chemical industry as solvents and also as chemical intermediates. The lactones can be converted to 1,4-diols, to tetrahydrofurans, and to pyrrolidone derivatives. For example, gamma-butyrolactone can be converted into 1,4-butanediol, tetrahydrofuran or pyrrolidone, all of which are important industrial chemicals.
Gamma-butyrolactones are manufactured presently by two principal methods. The first involves the sequence of reacting acetylene with formaldehyde to produce 1,4-butynediol, hydrogenating the 1,4-butynediol to 1,4-butanediol, followed by dehydrogenation to gamma-butyrolactone. The second primary method involves the hydrogenation of maleic anhydride or succinic anhydride.
German patent 1,066,572 teaches that trimethylene oxide can be carbonylated to produce gamma-butyrolactone in the presence of metal carbonyls as catalyst. Heck, J.Amer.Chem.Soc. 85, 1460 (1963) teaches that trimethylene oxide can be reacted with carbon monoxide and cobalt hydrocarbonyl to form 4-hydroxybutyrylcobalt tetracarbonyl, which, in turn, reacts with dicyclohexylethylamine to produce cobalt carbonyl anion and gamma-butyrolactone.
A new method of producing gamma-butyrolactones has been discovered which involves reacting olefins with aldehydes to obtain a 1,3-difunctional compound which is thereafter reacted with carbon monoxide to form the lactone which is subsequently recovered. The method of the present invention is advantageous in that lower cost starting materials can be employed and a much wider variety of gamma-butyrolactone derivatives can be produced.
Accordingly, it is the object of this invention to provide a new method for the manufacture of butyrolactones from olefins. This and other objects of the invention will become apparent to those skilled in the art from the following detailed description.